1. Field of the Invention
This invention relates to computer systems, and more particularly, the prevention of the leakage of electromagnetic energy through a computer system chassis.
2. Description of the Related Art
One important aspect in the design of computers and electronic systems is the shielding of electromagnetic energy. In the design of most electronic systems, it is desirable to shield the system from unwanted electromagnetic interference from external sources, as well as to contain electromagnetic energy generated by the system itself. Furthermore, certain government regulations (e.g., Federal Communications Commission requirements) may necessitate that electronic systems be designed to contain electromagnetic noise within certain specifications.
Computers and other electronic systems are typically contained within an enclosure that includes a chassis. Due to the operation of various components in such an electronic system, electromagnetic energy may be coupled to the chassis. This energy may translate into currents that are conducted on the interior of the chassis surface. While the chassis may be designed with a minimal number of slots and/or other apertures to contain internally generated electromagnetic energy from escaping (or externally generated electromagnetic energy from entering), apertures that may be present in the chassis may allow electromagnetic energy to enter or escape. For example, gaps in a computer system chassis may exist in locations where peripheral cards have been inserted (e.g., a PCI, or peripheral component interface, slot). Such gaps may allow electromagnetic energy to escape the chassis, or externally generated electromagnetic energy to enter the interior of the chassis. Such electromagnetic energy may lead to EMI.